Characterization of residual lignin in cellulose isolated by the diglyme method from three Pinus species by IR spectroscopy and analytical pyrolysis

Holzforschung ◽  
2018 ◽  
Vol 72 (2) ◽  
pp. 91-96 ◽  
Author(s):  
Ana Alves ◽  
Sara Santos ◽  
Rita Simões ◽  
José Rodrigues
Keyword(s):  
Pinus Halepensis ◽  
Lignin Content ◽  
Rapid Screening ◽  
Cellulose Content ◽  
Residual Lignin ◽  
Analytical Pyrolysis ◽  
Cellulose Yield ◽  
Screening Experiments

AbstractQuantitative determination of cellulose content by means of diglyme [bis(2-methoxyethyl) ether] isolation is useful for rapid screening experiments. However, diglyme isolation from softwoods results in a certain amount of residual lignin in the cellulose. In this paper, the lignin content (L) in diglyme cellulose of three pine species (Pinus halepensisMiller,Pinus sylvestrisL. andPinus pinasterAiton) was analysed by ATR-FTIR spectroscopy and analytical pyrolysis (Py). Py allowed lignin quantification. The influence of wood milling on cellulose yield was also analyzed and it was shown that a particle size between 10 and 60 mesh did not noticeably influence the cellulose yield or L; however, ball-milling to powder did cause a cellulose loss of around 37%. The diglyme method is only reproducible if the experimental parameters are standardized and meticulously followed.

Study of Residual Lignin in Pulp by UV Resonance Raman Spectroscopy

Holzforschung ◽  
2001 ◽  
Vol 55 (6) ◽  
pp. 631-638 ◽  
Author(s):  
M. Halttunen ◽  
J. Vyörykkä ◽  
B. Hortling ◽  
T. Tamminen ◽  
D. Batchelder ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Lignin Content ◽  
Resonance Raman Spectroscopy ◽  
Resonance Raman ◽  
Residual Lignin ◽  
Highly Sensitive ◽  
Uv Resonance Raman ◽  
Uv Resonance Raman Spectroscopy ◽  
Hexenuronic Acid

Summary A major problem in the development of new bleaching technologies for pulp is the difficulty of analysing the changes induced by bleaching chemicals in the structures of residual lignin. Separation and isolation of the residual lignin before the analysis may modify the constituents of interest, whereas if the pulp is analysed directly, the responses from cellulose and hemicelluloses will overlap the signal from the residual lignin. In this study, UV resonance Raman spectroscopy, a powerful technique for detecting trace components in complex mixtures, was applied to detect the changes in the residual lignin content after bleaching stages. The resonance Raman technique was found to be highly sensitive and selective for lignin structures allowing the detection of trace amounts of lignin after the final bleaching stages. Furthermore, it enabled rapid and easy determination of hexenuronic acid content. UV resonance Raman spectroscopy would appear to be a technique of great potential for pulping and bleaching research.

scholarly journals In situ determination of the syringyl/guaiacyl ratio of residual lignin in pre-bleached eucalypt kraft pulps by analytical pyrolysis

2015 ◽  
Vol 112 ◽  
pp. 164-172 ◽  
Author(s):  
C.F. Lima ◽  
L.C.A. Barbosa ◽  
Marcela N.N. Silva ◽  
J.L. Colodette ◽  
F.O. Silvério
Keyword(s):  
Kraft Pulps ◽  
Residual Lignin ◽  
Analytical Pyrolysis

scholarly journals Sintesis dan Karakterisasi Selulosa Asetat (CA)

2018 ◽  
Vol 5 (2) ◽  
pp. 58-62
Author(s):  
Fensia Analda Souhoka ◽  
Jolantje Latupeirissa
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Cellulose Acetate ◽  
Acid Anhydride ◽  
Degree Of Substitution ◽  
Synthesis And Characterization ◽  
Cellulose Content

Synthesis and characterization of cellulose acetate (CA) has been conducted. The cellulose used in this study was commecial a-cellulose in 92% content. All the CA products were analyzed by FTIR spectrometers. The determination of cellulose content was done using standart method of TAPPI T-203, while the determination of the degree of substitution (DS) was based on SNI 0444:2009 method. Conventional acetylation of cellulose was performed using gacial acetic acid, anhydride acetic acid, and sulfuric acid. The acetylation at 25 °C for 2.5 hours gave the DS of 1.482 and at 40 °C for 5 hours gave the higher DS 2.295.

scholarly journals Perbandingan Kandungan Selulosa dan Lignin dari Kayu Acacia crassicarpa dan Acacia mangium

2020 ◽  
Vol 1 (1) ◽  
pp. 12
Author(s):  
Melysa Putri ◽  
Shalsyabila Poeni
Keyword(s):  
Lignin Content ◽  
Gravimetric Method ◽  
Acacia Mangium ◽  
Chemical Compositions ◽  
Cellulose Content ◽  
Test Results ◽  
Dry Land ◽  
Acacia Crassicarpa

The development of the pulp & paper industries in Indonesia increase every year. To support the development of industries in Indonesia in order to be able to compete with similar industries from abroad, it is very important to pay attention to the quality of the paper produced. One way to determine the quality of the pulp & paper is by knowing the chemical composition and area where the wood grows. Important chemical compositions that can support the strength of wood and paper quality include cellulose and lignin. Therefore, this study was conducted to compare the levels of cellulose and lignin contained in Acacia crassicarpa wood from wetlands and Acacia mangium from dry land which is processed into pulp & paper with good quality. Determination of cellulose and lignin content in wood was carried out using the gravimetric method. Test results on Acacia crassicarpa wood species from wetlands obtained cellulose content of 55.48% and lignin 24.13%, while in Acacia mangium wood from dry land obtained cellulose content of 51.46% and lignin 27.66%. According to company standards that levels of cellulose and lignin in two different fields are obtained according to the standards set by the company. So for the results of testing Acacia crassicarpa wood from wetlands have the highest levels of cellulose with low levels of lignin

Characterization of Impressed Current Technique to Model Corrosion of Reinforcement in Concrete

2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin
Keyword(s):  
Immersion Time ◽  
Chloride Content ◽  
Engineering Science ◽  
Coastal Regions ◽  
Faraday’S Law ◽  
Current Technique ◽  
Corrosion Cell ◽  
Impressed Current

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99

The Determination of Sense via Deleuze and Blanchot: Paradoxes of the Habitual, the Immemorial, and the Eternal Return

2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  
Eternal Return

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.

SEM/EDS Characterization of Uncommon Metal Whiskers and Determination of Underlying Growth Mechanisms

2018 ◽  
Author(s):  
D. Basak ◽  
L. H. Ponce
Keyword(s):  
Reliability Analysis ◽  
Case Studies ◽  
Whisker Growth ◽  
Innovation Systems ◽  
Growth Mechanisms ◽  
Crystal Oscillator ◽  
Analysis Laboratory ◽  
Investigative Techniques

Abstract Two case-studies on uncommon metals whiskers, performed at the Reliability Analysis Laboratory (RAL) of Northrop Grumman Innovation Systems, are presented. The components analyzed are an Oven Controlled Crystal Oscillator (OCXO) and an Electromechanical Relay. Investigative techniques were used to determine the chemical and physical makeup of the metal whiskers and develop an understanding of the underlying effects and mechanisms that caused the conditions conducive to whisker growth.

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